Toggle drawing-press.



l. PATRICK.

TOGGLE DRAWING PRESS.

APPLICATION man APR. s. |911.

Patente Feb. 5, 1918.

4 SHEETS-'SHEET l.

I. PATRICK.

TOGGLE DRAWING PRESS. APPLICATION FILED APR. 6. 19u.

o SHEETS-SHEET 2.

l. PATRICK. Io'GGLE DRAWING PIIEss. APPLICATION PIII-:D AP'II. a. Ism.

/77 emfmem@ Peb. 5 IIIIP.

. PAHCK.

TOGGLE DRAWING PRESS. APPLICATION FILED APR. 1911.

. 4 SHEETS-SHEET 4.

Peeeeeeel Fee. 5,1918.`

Il l

ISAC PATRICK, MFHMS'IINGS, MICHIGAN, ASSIGNOR T0 CONSOLIDATED PRESS CUM- ]EANY, 0F HASTINGS, MICHIGAN, A CORPORATION 0F MICHIGAN.

'IOGGLE DRAWING-PRESS'.

Specication of Letters Patent.

Patented Feb.. 5, IFI..

llplcation led April 6, 1917. Serial No. 160,212'.

'ject of the King of Great Britain, residing at Hastings, in the county of Barry and State of Michigan, have invented certain new and useful Improvements in Toggle Drawing-Presses; and I hereby declare that the following is a full, clear, and exact description thereof, reference being had to the) accompanying drawings, which form part of this specification.

This invention relates to presses for drawing and stamping metal, and has particular reference to .the means for operating the blank-holder devices in such presses, and to the means for adjusting such devices.

'Ihe embodiment of the invention illustrated may be described in brief as a novel toggle-movement for operating the 4outer or blank-holder-slide of a toggle drawing press, so that such blank-holder-slide'will descend 'and engage the work and commence its dwell j before the crank operating the inner drawing slide or plunger has begun to operate on the work, and the blank-holder-slide will continue to dwell and hold the work until the drawing-slide has completed its downward stroke or work, aftefr which the blankholder-slide will rise preferably substantiall in unison with the drawing-slide until the' lank-holder-slide has completed its up stroke.

rIhe invention further includes novel means for adjusting the blank-holder-slide as a whole to suit diferentthicknesses of material of work to be operated upon; and also means for independently adjusting parts of the blank-holder to prevent unequal strains thereon.

I will describe one-practical embodiment of the invention, as illustrated in the accompanying drawings, so that the same may be fully understood by those lfamiliar with the art, and will summarize in the claims following such description, the essential features and combinations for which protectionis desired; but I do not consider the invention' restricted, to the specific form or; construction of parts illustrated in thedrawings.

In said drawings: Figure 1 is a partial front elevation of a toggle-drawing press with my novel blankholder-operating mechanism applied thereto.

Fig. 2 is apartial side view of Fig. Lillusytrating more particularly the blank-holderoperating mechanism in elevation.

Fig. 3 is a detail top plan view of Fig. 2.

' Fig. 4 is an enlarged detail vertical section on the line 4 4 Fig. 2.

Fig. 5 is a detail view showing the plunger or drawing-slide approximately on half stroke, vand indicating the blank-holder-slide at the beginning of its dwell or end of down stroke.

Fig. 6 is a transverse section on line 6-6 Fig. 5.

Fig. 7 is a detail View of the rack-yokes y N, O, and pinion II.

Fi 8 and 9 are smaller front elevations of the parts for operating the blank-holderslide and adjusting same, partly in section and detached; the parts being illustrated in diderent positions in the two figures.

The invention may be applied to various forms of drawing or stamping presses, or toggle-presses now in use; and such a press is conventionally shown in part in the drawings; in which'A represents the plunger or drawing-slide, of a well known type` of drawing press, connected in the usual manner by av pitman A to a crank B on a crank shaft B journaled in the main frame 1 of the press; and which shaft may be rotated by gearing in the usual manner, so as to reciprocate the drawing-slide during each rotation of said shaft B.,

Coacting with the drawing-slide is a blank-holder-slide, which may be of any suitable construction, adapted to hold the stock or work during the drawing or stamping operation thereon; and said blankholder-slide must, therefore, dwell or remain stationary during such operation.

In accordance with' my invention the' blank-holder-slide` is operated by toggle-` links and connections so arranged that they `will first lower the' blank-holder-slide onto the work and hold it 'at rest thereon during the drawing operation, and thereafter lift the blank-holder-slide on the up stroke. of'

the drawing-slide to permit the operator to remove the drawn shell or stamping, or insert a new blank in the die ready to be drawn or stamped.

The blank-holder-slide C is shown as adjustably connected, as hereinafter described, to bars' W, eachsof which is pivotally connected at its ends (see Fig. 2) to the lower gear H'which has a ends of links lV, which are in turn otally connected at their upper ends to arms U on rock shafts T, journaled in bearings2 on the frame 1, two of said shafts being piv- The rock shafts T, carry arms S, from which are suspended links P, v.to which are pivotally connected links Q; these links Q are pivotally connected at their lower ends to brackets R, on the main frame of the ma' chine, as indicated in Fig. 1. p n

To the bolt p that pivotally connects the iinks P 'and o at the left hand sidetf the machine is also pivotally connected the shank of a yoke member N ywhich embraces a shaft 3 journaled in the main frame and in the end ofva bracket 4 attachedy to said frame. Yoke N carries a .rack N 'which enga es with a pinion K onfthe 'shaft 3. i

o the bolt pf connecting. links P, Q at the right hand side of the machine is also pivotally connected the shank of a yoke member O which also embraces. pinion K' and has a rack O engaging said Ypinion at, lthe Side opposite the rack N', see Figs. 2 and 7. v

On the shaft 3 is also mounted a second reduced-hub portion H. Said pinion H meshes with a rack G, on yoke F 'that embraces the pinion H, and said yoke has a reduced slotted portion J that embraces the hubHiof the pinion H and insures constant mesh of rack G therewith. The yoke F also has a slot F which slidably engages the preferably reduced end B2 of the shaftv B, and is retained slidably in en# gagement' therewith by means of a collarX sultably secured tol the'end B2 of shaft B.

' any a race cam and its groove D v`1t causes said pinion to `cam DI is mounted on the shaft B ad- ]acent the yoke F. Said cam is preferably is engaged by a roller on a stud E attached to the yoke F, so that yoke F willbe raised and lowered b the action of the cam D; and as the rack on said yoke is in mesh with pinion H,

rock or turn alternately backward and forward.

The pinion K is made fast to pinionH, in suitable manner, So thatit must rotate therewith; and when Vpinion His turned pinion K turns therewith and will through racks N', ,Of move the yokes N and O oppositely, outward or inward as the case may be; and these yokes toggles formed bly links Q and will stralghten or brea such toggles.

The straighteningjor bre'a gles P',

causes' av corresponding rocking movement ofthe related shafts T, through ar ranged at opposite sides of the main frame. l

motion to rack yokes operate the opposite f ates yoke F which straight line (owin to the extensions on pinion H and crank 51 the slots in said yoke). The yoke F causes pinions H vand ,K to revolve, and impart N and O which in turn operate toggles P, Q; which in turn cause \cranks S to move in accordance therewith and rock shafts T and through toggles U, V raise or lower the blank-holder-slide, see Fi s.land2.

t is obvious that the cam surface of the cam D can be shaped to impart any desired movement or dwell to the blank-holderslide during the rotation of said cam; also that when the blank-holder-slide is at the lower end of its stroke, and durin the time that thework is bein .performe the tog( gles formed by links Q and the toggles formed by arms U, and links V are in straight or unyielding position, and are so held by the rack yokes N and O controlled by pinions H, K and cam D;.said toggles firmly resist any upward pressure exerted on the blank-holder-slide and cause it to hold the stock securely and properly durin the leffective part of the working stroke o the drawing-slide. Preferably, as in the construction shown, all the wrist pins or pivot bolts in the toggle mechanism are supported in double shear or at both ends, thus preventing any tendency of the toggles4 to weave. or deflect laterally vwhile under pressure; and insuring a4 perfect dwell during the drawing stroke.

The outer end of the shaft 3l carrying the pinions being supported by a substantial bracket A Isaid shaft strains to which it is subjected without deflection.

The racks or rack yokes N and O preferably have a toothless member opposite to the rack sliding in perfect mesh with said pinion, see Fig. 7; and no matter what position relative to their pivots R on brackets R the links Q may assume, the rack yokes O, N lie always radially of the shaft 3 carrying the pinion K.

The means shown for adjusting the blankholder-slide are as follows: Two depend'- ing threaded rods a, are connected to each bar,` W in any suitable manner. As shown each rod has a shoulder va below the bars W,

. p and is fastened thereto by nuts a2, a8 screwed g of the togon the threaded upp'er end of the rod above the bar, (see Figs. l, 2, 8 and 9).

These rods a respectively pass through,

brackets or -lugs C on the sides of the blank-holder-slide C and are engaged with` internally threaded nuts b belowthe lugs C which nuts preferably ,havel circular portions entering the lugs C to steady the nuts relative thereto,

upon the pinion K and` thereby keeping their rack members N', O

must vreciprocateon a aft B passing through can withstand lthe (see Fig.A 2,) and said nuts E are provided with worm gears b by which the nuts may be turned to adjust the rods a.

Screwed on each rod a above the lug C. are adjusting and locking nuts d, d; and

below the worm b on each rod a are ad-.

justing and'locking nuts e, e.

In the example shown there are four of these rods a connected with the blank holder C, two at each side thereof; and the rods a at opposite sides ofthe blank-holder are preferably connected to the same bar W.

j worms g are arranged yat both front and back of the blank-holder-slide.

0n one end of each worm shaft g is a spiral or helical gear g2 which meshes with a helical gear h2 mounted on a shaft h, running through the blank-holder from front to back, or otherwise suitably journaled thereon; said shaft is provided with suitable means for rotating it; a hand wheel z. being shown. a

`Whenl it is desired to adjust the blankholder upwardly the nuts d, d lare loosened; if the blank-holder is to be adjusted downwardly nuts e, e are loosened. The hand wheel h `is then turned so as to cause worms h2 to turn shafts g and cause worms g to rotate the worm gears b in the desired direction to raise, or lower, the blank-holder relatively to the bars W.

As the blank-holder is .suspended on the rods a by the worm nuts b, it follows that as these nuts are raised or lowered on the rods, the blank-holder-slide is similarly adjusted to osition. After the blank-holder-slide is adj sted all the nuts should be securely tightened.

If after the blank-holder-slide has been adjusted to suit the general requirements, it isr necessary to adjust any particular corner of the blank-holder to hold more securely at that point the sheet, or work to be drawn, the nuts 0.2, a3 on the adjacent rod are loos ened and a wrench applied to the yhexagon portion a of such rod, and it is turned until the desired adjustment is obtained. Then nuts a2, a3 are tightened.

By. this construction in addition to means for simultaneously adjusting all the rods a, each rod can be individually adjusted; and this saves much time and inconvenience in adjusting the blank-holder to suit different thicknesses of work or blanks, and also obviates straining the blank-holder by unequal adjustment.

The novel toggle movement described for operating the blank-holder-slide is compact,-

and powerful. It can be readily locatedon the upper part of the press 1n a pos1t1on where the operatorv is in no danger from moving parts; and whereit will not prevent or obstruct the free access by the operator to all par/ts of the press.

With thisrinvention any desired stroke and time of the dwell of the blank-holderslide can be obtained by properly designing the cam D and the stroke and dwell of the blank-holder can be varied to suit different kinds of work by changing the said cam for one designed to suit such work. And the blank-holder-slide can be readily adjusted to suit the particular kind of blank to be operated upon.

lVhat I claim is:

l. In a press, the combination of a drawing-slide, means for reciprocating the slide;

-a blank-holder, a rock shaft, links connecting said shaft with the blank holder, a toggle connected with the shaft and with a relatively fixed point, a rocking pinion, a rack bar engaging the said pinion and connected with the toggle to straighten or break same, and means for oscillating said pinion.

2. In a press, the combination of a drawing-slide, means for reciprocating the slide, a blank-holder-slide, a rock shaft, a toggle pivotally connected with said shaft and with the blank-holder-slide, a second toggle connected with the shaft and with a'relatively fixed point, a rocking pinion, a rack bar engaging the said pinion and connected with the second toggle to straighten or break same,and cam actuated means for oscillating said pinion. l

3. In a drawing press, the combination of a drawingslide, means for reciprocating said slide; a blank-holder, rock shafts at opposite sides of the machine, links connecting said shafts with the blankaholder; toggles respectively connected with the said shafts and with relatively fixed points, a rocking pinion, a rack engaging said pinion, and connected with the toggle to straighten or break same, and means for oscillating said pinion.

4. In a drawing press the combination of a drawingslide, means for reciprocating said slide; a blank-holder-slide, rock shafts at opposite sides of the machine, toggles pivotally connecting said shafts with the blankholder-slide; second toggles respectively connected with the said shafts and with relatively fixed points, a rocking pinion, a rack engaging said pinion, and connected with the second toggle to straighten or break same, and cam actuated means for oscillating said pinion.

5'. In a drawing press the combination of a drawing-slide, means for reciprocating said slide; a blank-holder-slide, rock shafts at opposite sides of the machine, links pivotally connecting arms on said shafts with the blank-holder-slide, toggles respectively connected with the said shafts and with relatively fixed points, a rocking pinion, rack -thef toggle and saidy rack so that the toggle is straightened or broken by the action of said rack; and connections between said rock connected with j and shaft and the blank-holder-slide for operating the latter.

'7. In combination with a press having a drawing-slide, and a blank-holder-slide; of means for operating the blank-holder-slide comprising an oscillatory pinion, a rack engaging said pinion, a rock shaft, connections between said rock shaft and the blankholder-slide for operating the latter; an arm the rock shaft, a toggle having one member pivotally connected to the arm of the rock shaft the other member pivotally connected to-a relatively xed support, a connection between the center pivot of the toggle and said rack so that the toggle is straightened or broken by the action of said rack; and a cam and connections for operating the oscillatory pinio 8. In combination with a drawing-press having a reciprocating plunger, a main shaft connections for operating said plunger, and a work-holder-slide; of means for'operating said work-'holder-slide comprising opposite rock shafts mounted on the frame of the machine, arms on said shafts, links connecting the arms on said shaft with the workholder-slide,

toggles pivotally connected with arms on said shafts, and with relatively fixed pivots, an oscillatory pinion, and racks engaging opposite sides of said pinion and extending in opposite directions and respectively connected with the pivot joints of the toggles to straighten or break same; and means for oscillating said pinion.

9. In combination with a drawing-press having a reciprocating plunger, a main shaft and connections for operating said plunger, and a work-holder-slide; of means for operating said work-holder-slide comprising opposite rockl shafts mounted on the frame of the machine, arms on said shafts, links connecting thew arms on said shaft with the work-holder-slide, toggles pivotally connected with arms on said shafts, and 'with relatively iixed pivots, an oscillatory pinion, rack yokes engaging opposite sides of said pinion and extending in opposite directions and respectively connected with/the pivot j arms on said shafts and with relatively fixed pivots; an oscillatory pinion; rack yokes engaging opposite sides of said pinion and extending in opposite directions and respectively connected with the toggles to straighten or break same, a rack for oscillating said pinion, and means for recipr cating said latter rack, substantially as described.

l1. Ina drawing press, the combination of a drawing-slide, a main shaft and con-` nections for reciprocating said drawingslide; of a work-holder-slide; a pair of parallel shafts mounted on'the machine, arms connected with said shafts, links connecting said arms with the work-holder-slide; other' arms connected with said shaft, a pair of toggle links respectively connected with the latter arms on the shafts and with fixed pointswon the frame, an oscillatory pinion intermediate the said toggles, oppositel disposed racks respectively connected wit the toggles and engaging opposite sides of said oscillatory pinion, a slidable 'rack for oscil- 100 lating said pinion, and a cam and means operated `by said cam for reciprocating said slidable rack.

12. In a drawing press, the combination of a reciprocating drawing-slide, a main 105 shaft and connections for reciprocating said drawing-slide, and a work-holder-slide; of means for operating the work-,holder-slide comprising a pair of parallel shafts mounted on the machine above the work-holder-slide, 11o arms connected with said shafts, links connecting said arms with the work-holderslide; other arms connected with said shaft, a pair of toggles respectively connected with the latter arms on the shafts and with fixed points on the frame; an oscillatory pinion intermediate the said toggles, oppositely disposed rack-yokes respectively connected with theknee pivots of the toggles and engaging opposite sides of said osclllatory pinion, a slidable rack for oscillating said pinion, a

-rotatable racey cam, and means connected said shaft and with a relatively tXed point, and cam actuated means directly connected with the pivot joint of the latter toggle for straightening or breaking such toggle.

14. In combination With a press having a reciprocatory drawing-slide, and means for operating said slide; a blank-holder-slide, a rock shaft, a toggle connecting the rock shaft With the blank-holder-slide, a second toggle pivotally connected With the shaft and wlth a relatively fixed point, a member pivotally connected With the pivot joint of the second toggle, and a cam actuated means for operating said member to cause it to straighten or break the toggle.

15. In combination with a drawing press having a reciprocatory drawing-slide, and means for operating said drawing-slide; of a Work-holder-slide adapted to hold the Work While the drawing-slide is operating thereon, a pair of rock shafts, toggle-links connecting the rock shafts with the blank- 4 holder, arms on said shafts, toggles pivotally connected with the arms on said shafts and with relatively fixed points, members directly connected with the pivot joints of the latter toggles, and means for operating said members to straighten or break such toggles, substantially as described.

16. In a drawing press, a reciprocatory drawing-slide, means for operating said drawing-slide; a work holder adapted to hold the Work while the drawing-slide is operating thereon, a pair of rock shafts provided with arms, links connecting arms on the rock shafts with the blank-holder-slide, toggles respectively pivotally connected with other arms on said shafts and With relatively fixed points, members directly connected with the pivot joints of the toggles and means for actuating said members to straighten or break the toggles, substantially as described.

In testimony that I claim the foregoing as my own, I affix my signature.

ISAAC PATRICK. 

